'Bitterness' in the Bible

The Israelites turn justice into bitterness; they throw what is fair and right to the ground.

"Horses don't run over bare rock, do they? One doesn't plow rock with oxen, does he? But you have turned justice to gall, and the fruit of righteousness into bitterness.

And have turned your festivals to mourning, And all your songs to lamentation, And caused sackcloth to come up on all loins, And on every head -- baldness, And made it as a mourning of an only one, And its latter end as a day of bitterness.